Set special users before automatic run stops

A minimal, but not comprehensive addition for OCTRL-1065.

Author: knopers8

common/protos/common.pb.go

@@ -40,6 +40,15 @@ message User {
   string name = 3;
 }
 
+// Production and staging BKP recognizes these special user IDs.
+// They are used to associate certain actions (e.g. EOR) with certain subsystem
+// or AliECS component rather than a human user.
+enum SpecialUserId {
+  INVALID = 0;
+  LHC = 60;
+  TIMER = 65;
+}
+
 message WorkflowTemplateInfo {
   string name = 1;
   string description = 2;

common/protos/common.proto

@@ -34,3 +34,17 @@ func WrapEvent(ce isEvent_Payload) *Event {
 		Payload:   ce,
 	}
 }
+
+// SpecialUser returns a User populated from a SpecialUserId enum:
+// - externalId = enum numeric value
+// - id = enum numeric value
+// - name = enum string name
+func SpecialUser(enumId SpecialUserId) *User {
+	externalId := int32(enumId)
+	name := enumId.String()
+	return &User{
+		ExternalId: &externalId,
+		Id:         nil,
+		Name:       name,
+	}
+}

common/protos/protoutils.go

@@ -1460,6 +1460,7 @@ func (env *Environment) scheduleAutoStopTransition() (scheduled bool, expected t
 					log.WithField("partition", env.id).
 						WithField("run", env.currentRunNumber).
 						Infof("Executing scheduled auto stop transition following expiration of %s", autoStopDuration)
+					env.SetLastRequestUser(pb.SpecialUser(pb.SpecialUserId_TIMER))
 					err = env.TryTransition(NewStopActivityTransition(ManagerInstance().taskman))
 					if err != nil {
 						log.WithField("partition", env.id).

core/environment/environment.go

@@ -1113,6 +1113,7 @@ func (envs *Manager) handleLhcEvents(evt event.IntegratedServiceEvent) {
 					WithField("run", env.currentRunNumber).
 					Info("stopping the run due to beam dump")
 
+				env.SetLastRequestUser(evpb.SpecialUser(evpb.SpecialUserId_LHC))
 				err := env.TryTransition(NewStopActivityTransition(envs.taskman))
 				if err != nil {
 					log.WithPrefix("scheduler").